Restore a pause_at() method, but for NetDocReader.

tor-netdoc/src/routerdesc.rs

@@ -228,13 +228,11 @@ impl RouterDesc {
         Section<'a, RouterKW>,
         Section<'a, RouterKW>,
     )> {
-        use crate::util::*;
         use RouterKW::*;
 
         // Parse everything up through the header.
-        let mut reader = PauseAt::from_peekable(reader.iter(), |item| {
-            item.is_ok_with_kwd_not_in(&[ROUTER, IDENTITY_ED25519])
-        });
+        let mut reader =
+            reader.pause_at(|item| item.is_ok_with_kwd_not_in(&[ROUTER, IDENTITY_ED25519]));
         let header = ROUTER_HEADER_RULES.parse(&mut reader)?;
 
         // Parse everything up to but not including the signature.

tor-netdoc/src/tokenize.rs

@@ -6,6 +6,7 @@
 
 use crate::argtype::FromBytes;
 use crate::keyword::Keyword;
+use crate::util::PauseAt;
 use crate::{Error, Pos, Result};
 use std::cell::{Ref, RefCell};
 use std::str::FromStr;
@@ -539,4 +540,25 @@ impl<'a, K: Keyword> NetDocReader<'a, K> {
     pub fn iter(&mut self) -> &mut std::iter::Peekable<impl Iterator<Item = Result<Item<'a, K>>>> {
         &mut self.tokens
     }
+    /// Return a PauseAt wrapper around the peekable iterator in this
+    /// NetDocReader that reads tokens until it reaches an element where
+    /// 'f' is true.
+    pub fn pause_at<F>(&mut self, f: F) -> PauseAt<'_, impl Iterator<Item = Result<Item<'a, K>>>, F>
+    where
+        F: FnMut(&Result<Item<'a, K>>) -> bool,
+    {
+        PauseAt::from_peekable(&mut self.tokens, f)
+    }
+    /// Return a PauseAt wrapper around the peekable iterator in this
+    /// NetDocReader that returns all items.
+    #[allow(unused)]
+    pub fn pauseable(
+        &mut self,
+    ) -> PauseAt<
+        '_,
+        impl Iterator<Item = Result<Item<'a, K>>>,
+        impl FnMut(&Result<Item<'a, K>>) -> bool,
+    > {
+        self.pause_at(|_| false)
+    }
 }